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Six Is the Sum

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?

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(w)holy Numbers

A church hymn book contains 700 hymns. The numbers of the hymns are displayed by combining special small single-digit boards. What is the minimum number of small boards that is needed?

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In the multiplication calculation, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?

Number Detective

Stage: 2 Challenge Level: Challenge Level:1

Follow the clues to find the mystery number from the list below.

Inspector with magnifying glass.

  • The number has two digits.
  • Both of the digits are even.
  • The digit in the tens place is greater that the digit in the ones place.
  • The ones digit is not in the three times table.
  • The tens digit is not double the ones digit.
  • The sum of the two digits is a multiple of five.

18 & 86, 120 & 42, 46 & 64, 80 & 8, 22 & 83.